Indicators, not

[JohnD]

I think someone above pointed out that an LED needs only a tiny current, and I used one as a test light.   It flashed, so I had found 'volts' at the output of the flasher relay and at the steering column.   But today I used the Multimeter, and while I have battery volts (13.4V) going into the flasher relay, what comes out of the relay to the wire to the steering column is only 2.5V!   

It's a brand new relay.    I've wired it as shown, adding the black Earth lead that wasn't originally on the car.  The diagram is from the supplier's website, and I have added the wire colours

 

Also;

A/ the output on LG/B wire to steering column oscillates, 0V-2.5V-0V-2.5V ..... continuously, and no 'click'.

B/ there is a similar flashing voltage on the LG/P wire to the dashboard  jewel light, which doesn't shine.

 

Is the lack of illumination because the volts are too low to light up the bulbs?    Both dashboard jewel and the actual indicators which all expect about 12V?

Why the low output voltage?     Is this another 'wrong' relay, designed for LEDs?

And why does the relay 'flash' all the time?  Is this normal?

Weirdly, when I first turned the indicators on after replacing the bonnet, before I replaced the original flasher relay, they worked!  Then, they didn't!

So confused!

John 

 

[DeTRacted]

I have a 140103 on my car and it doesn't do that. 

Try removing the wire from C and connecting an LED bulb direct from C to earth and see what happens. 

[JohnD]

That's how I tested it!

Made up a test lead with female connector on it, substituted it for the 'green/brown' wire and put the LED between that and Earth.   Flashed.

When I tested today, I used the 'needle" probe on my multimeter. Fluctuating voltage on-off at 2.5V.

John

[DeTRacted]

You may be being mislead by the meter John - they draw next to no current so show voltage where there really isn't any with a load connected. Trying the bulb again does it still work?

[thebrookster]

3 hours ago, DeTRacted said:

You may be being mislead by the meter John - they draw next to no current so show voltage where there really isn't any with a load connected. Trying the bulb again does it still work?

Indeed, or might be worth fitting the bulb inline, and test the voltage across it (IE meter in parallel). 

(I am right in thinking voltage is same for parallel, or am I making an idiot of myself?)

[JohnD]

13 hours ago, DeTRacted said:

You may be being mislead by the meter John - they draw next to no current so show voltage where there really isn't any with a load connected. Trying the bulb again does it still work?

This confuses me further.    You say that a meter may show volts "where there really isn't any with a load connected".     But this was testing the main output of the flasher unit, supplied with battery volts, and putting out either 2.5V or, by your argument, almost none at all.    You are avoiding the real question, why does the flasher relay output such a low voltage, so low as to be only able to flash an LED and not old fashioned bulbs?

The bulbs ARE inline, Phil, and fitted to the bonnet.   And they don't flash.

JOhn

[DeTRacted]

1 hour ago, JohnD said:

You are avoiding the real question, why does the flasher relay output such a low voltage, so low as to be only able to flash an LED and not old fashioned bulbs?

Two possibilities John 

1/ the flasher unit has been damaged perhaps through an overload

2/ the voltage you see on the meter is spurious and you have assumed this low voltage was driving the bulb in the earlier test. 

Unless the measurement was made with a load ( i.e. bulb) attached to the output terminal, the reading you saw might just be due to leakage currents inside the relay and not a 'real' output at all.   I believe the RIPCA 7103 (which is that flasher unit) does not have physical contacts inside but uses semiconductor switches so there is bound to be some current leakage.  A DVM will happily lie to you by showing that as a voltage, but with a load connected the voltage may fall to near zero because it is actually coming thorough a high impedance.  

I suggest you re-connect your test bulb and measure the voltage across it.  It is likely that with that load the flasher will work properly at 12v output because the output transistors will switch properly with a reasonable load.

 

 

 

Edited September 22, 2023 by DeTRacted

[flatter4]

19 hours ago, DeTRacted said:

You may be being mislead by the meter John - they draw next to no current so show voltage where there really isn't any with a load connected. Trying the bulb again does it still work?

Yep ....
and remember the flasher circuit is on-off, and a cheap DC multimeter will get confused and average an oscillating voltage to show a low value.
Use a test bulb.

[RedRooster]

Buy a Fluke 

[JohnD]

Thank you, DTR and Flatter4!   Every day's a school day!

I fear that I must (and I will and do!) take what you say on trust, DTR, it's all Greek to me!   When  you say, measure the volts across a test lamp, this is with the probes from my meter on either side of the bulb?     And the bulb may be earthed anywhere?  I'm trying to follow the Volts through the system to isolate the fault, so to have a 'moveable' test set-up will be most helpful.

Flatter, I appreciate (maybe not 'understand'!) what you say, but I clearly saw the  figures go 0V...2.5V ... 0V... and the frequency was what you might expect from an indicator, a little bit more than once a second.     Is that too much for a multimeter?

The "Voltage regulator" that supplies the fuel and temp gauges on Triumphs chops the battery volts into segments, to average 10V.  (I am astonished that the above device is called a "regulator", when in fact it's output is 14V(about) .. 0V.. 14V .. 0V and so on.   I have a transistorised 'regulator' now, that of course merits the name and supplies 10v.............................10V!)   I recall seeing that oscillation clearly on my multimeter, either this one or a previous one, and at about the same frequency.   So I hope that I was seeing reality !   But I will do as DTR suggests.  I used to have a test lamp on a lead, but can't  find it now, that was why I was using the LED on a lead!   I must make one up - for all my electric buffoonery, I can solder!

John 

[DeTRacted]

1 minute ago, JohnD said:

When  you say, measure the volts across a test lamp, this is with the probes from my meter on either side of the bulb?     And the bulb may be earthed anywhere?

Yes John, the meter 'floats' electrically so the earth can be anywhere.  But if you have a bulb which lights up properly, measuring the voltage is probably somewhat redundant.  As I said some time ago (and others here too) often the best tool for tracing electrical faults on car wiring is a bulb with wires attached. 

[Escadrille Ecosse]

47 minutes ago, DeTRacted said:

often the best tool for tracing electrical faults on car wiring is a bulb with wires attached. 

This ^^^^

[RedRooster]

This twice

[JohnD]

Gosh, that seems so .... analog! But I bow to those who understand electrons!

John

[DeTRacted]

The real world is analogue John - with infinite resolution in X,Y,Z  and temporal vectors.  Digital is only an approximation to the nearest least-significant-bit . 

[RedRooster]

Electronics went to shit when it changed to digital. 

[Escadrille Ecosse]

18 minutes ago, RedRooster said:

Electronics went to shit when it changed to digital. 

They are clever but you can only do so much with FFT (fast Fourier transforms)

[JohnD]

1 hour ago, Escadrille Ecosse said:

They are clever but you can only do so much with FFT (fast Fourier transforms)

I ... can analyse torsion vibration in crankshafts.  With FFT!

[DeTRacted]

Back in the day you could do that with analogue kit but nowhere near as fast nor with anything like the resolution. It involved banks of discrete filters - usually magnetostrictive - one for each frequency band, mounted in 19-inch racks that filled a room.   It took days to do a test that you can do in minutes with FFT on a PC. 

[JohnD]

20 hours ago, DeTRacted said:

Yes John, the meter 'floats' electrically so the earth can be anywhere.  But if you have a bulb which lights up properly, measuring the voltage is probably somewhat redundant.  As I said some time ago (and others here too) often the best tool for tracing electrical faults on car wiring is a bulb with wires attached. 

OK, DTR!  I have made up a test bulb.  A small one, probably sidelight sized, and it lights up when connected to the battery.    I have used it to check the Flasher relay, as follows. 

When connected at the fuse box between the connection to the flasher relay and an Earth - it lights up. (Multimeter - 13V)

When connected to the input at the flasher relay - it lights up. (Multimeter, 13V)

When connected to the output from the flasher towards the steering column  switch - it does NOT light up.   (Multimeter 2.3V, both directly from the output to Earth, and when the meter probes are either side of the bulb)

 

Seems pointless to pursue these poor little volts further down the system, when they can't get through the flasher relay, so I turn to your expertise.    What's wrong?  It's a brand new flasher relay, as recommended by you!

John

[DeTRacted]

1 hour ago, JohnD said:

When connected to the output from the flasher towards the steering column  switch - it does NOT light up

How about if you connect it between the flasher relay output and earth?  

I read your description as it being in series with the switch and whatever other bulbs you still have connected so if that is right I'm not surprised it doesn't light. 

We know the flasher was OK initially, as you tested with the LED bulb. 

Edited September 23, 2023 by DeTRacted

[thebrookster]

On 9/22/2023 at 4:18 AM, JohnD said:

The bulbs ARE inline, Phil, and fitted to the bonnet.   And they don't flash.

Sorry, John, too long in silly heat is having an effect on my ability to construct coherent sentences! I was referring to the test bulb, not your indicators.

But tis all irrelevant now anyway, as you have several guys whom have explained what I meant for more eloquently than I ever could. I can do electronics, but in comparison to the gents above I am a hamfisted apprentice  Hence I shall join you in the "audience" and hope I understand what is being said!

[RedRooster]

John, just disconnect everything, then start with power and returns, measure what you have then add the circuit bit by bit. 

[JohnD]

2 hours ago, DeTRacted said:

How about if you connect it between the flasher relay output and earth?  

I read your description as it being in series with the switch and whatever other bulbs you still have connected so if that is right I'm not surprised it doesn't light. 

We know the flasher was OK initially, as you tested with the LED bulb. 

1/ "How about if you connect it between the flasher relay output and earth?  "  That's what I did!   No flash and 2.3V

2/ "in series with the switch and whatever other bulbs you still have connected"  No, I've made up a temporary wire with a female terminal, taken out the wire to the steering column out, and inserted the temp wire, so that the flasher contacts it, and I could  test it with the bulb, between the flasher and Earth! As suggested!    I KNOW the other bulbs aren't working, which is why I worked down from the fuse which was good.

3/ "We know the flasher was OK initially, as you tested with the LED bulb. "   Yes, but as you said, an LED works with a very small voltage! My preference for actual measurement, with the meter which showed a very small voltage,  rather than the test bulb which lit up despite the few volts, demonstrates, I fear, a disadvantage of analogue!   At least the fault has been isolated to the flasher relay, unless my wiring of it is at fault?

John

Edited September 23, 2023 by JohnD

[DeTRacted]

15 minutes ago, JohnD said:

Yes, but as you said, an LED works with a very small voltage!

No I don't think I said that John. LEDs work with a very small current - rather different thing. 

If the LED bulb lit up properly and flashed originally, it was probably getting the correct voltage and the flasher unit was working.  Again, you are assuming that the low voltage you measured later, was also there originally rather than 12v. Maybe something happened to the flasher unit when it was connected to the rest of the circuit ? It is rated for a maximum of 30W load which at 12v is 2.5 Amps. 

I any case on the basis of your tests I think it is reasonable to assume the flasher unit is now, unfortunately,  dead  .  

It would be useful to check that the rest of the indicator circuit is operational.  You could do that by connecting 12v direct to the wire from the indicator switch - via an in-line 5A fuse just in case there is a short circuit.  Switching the indicators should then light up the relevant lamps on each side though they will be lit continuously of course.